package follow.pratice.in2020.November.javaguide.basis.demo1;

import java.util.HashMap;
import java.util.TreeMap;

public interface Caes_3 {
    public static void main(String[] args) {
        StringBuffer string = new StringBuffer("hello world");
        string.append(123);
        System.out.println(string);


        StringBuilder builder = new StringBuilder("hello python");
        builder.append("c++");
        System.out.println(builder);
    }


}
